The present invention is related to a flash memory device and a method for manufacturing the flash memory device.
A non-volatile memory device may be implemented using split-gate flash technology. In performing a programming operation on a split-gate flash memory device, a high positive bias may be applied to the control gate (CG), such that hot electrons may be injected from the source through an oxide layer into the floating gate (FG). In performing an erasing operation on a split-gate flash memory device, a high negative bias may be applied to the control gate, such that hot electrons in the floating gate may take advantage of Fowler-Nordheim tunneling to travel through a sidewall oxide layer into the erase gate (EG). Because of Fowler-Nordheim tunneling effect, for a split-gate flash memory device, an erasing operation may require substantially longer time than a programming operation. The efficiency of erasing operations of a split-gate flash memory device may be unsatisfactory.